1. Field of the Invention
This invention relates to a line for use in body fluid treatment using such a body fluid treating apparatus as an artificial kidney or an ascitic fluid treating apparatus, which line comprises a tubular member for connecting such apparatus to a patient and other necessary constituent members of the treating system.
2. Description of the Prior Art
In operating an apparatus for the extracorporeal treatment of a body fluid, such as blood or ascitic fluid, a line device for leading the body fluid to the apparatus and then back to the body is generally used. The line device comprises a tubular member, which serves as the passageway for the body fluid, and as necessary a pressure monitor means, a pressure adjustment means, a bubble removing means, a filter means, a sampling or drug addition means, etc. Among these means, the conventional pressure monitor means (cf. FIG. 1) is connected with a drip chamber, which serves as a bubble removing means, and the pressure gauge is actuated by means of the air within an air reservoir disposed in the line. In the conventional body fluid treatment, heparin is added to the body fluid to prevent the fluid from coagulation (in case of the blood, from clotting) or urokinase is added to dissolve coagulates or clots, so that the provision of an air reservoir or chamber in the line does not produce any problems.
However, it is recently pointed out that the use of the above-mentioned anticoagulant and other agents causes and increase in physiological load on the patients' side and an increase in bleeding tendency in patients (e.g. in post-operative dialysis or dialysis in females in the menstrual phase). Thus it is said that reduction in quantity or nonuse of such anticoagulant or the like is desirable. When a body fluid is treated with a reduced quantity of an anticoagulant or without use thereof (hereinafter collectively referred to as "reduction in quantity"), the provision of a space in which air is present, such as an air reservoir, in the line must be avoided strictly, since body fluids are easy to coagulate upon exposure to air. Accordingly, it has become necessary to provide a pressure detecting means which avoids contact of body fluids with air and can be used as a substitute for the conventional air-actuated pressure detecting means in the conventional line.